270 PYOGENIC BACTERIA. 



quantity of an agar culture was suspended in 0. 5-per-cent salt solu- 

 tion, and this was rubbed upon the uninjured skin of the left fore- 

 arm. By gentle scratching with a disinfected finger nail the epithe- 

 lium was removed in places over the area to which the micrococcus 

 had been applied. As a result of this procedure numerous impe- 

 tigo pustules and occasionally a genuine furuncle developed. Por- 

 tions of the skin containing the smaller pustules were excised and 

 examined microscopically. As a result of this examination Bock- 

 hart concluded that the cocci penetrate by way of the hair follicles, 

 the sebaceous and sudoriparous glands, or, where the epidermis had 

 been removed by scratching, directly to the deeper layers of the skin. 



In Bumm's experiments, made upon himself and several other 

 persons, Staphylococcus aureus suspended in sterilized salt solution 

 was injected beneath the skin. An abscess resulted in every case. 



The very extended researches made by bacteriologists during the 

 past five or six years show that the golden staphylococcus is the 

 most common pyogenic microorganism. Its presence has been de- 

 monstrated not only in furuncles and carbuncles, but also in various 

 pustular affections of the skin and mucous membranes impetigo, 

 sycosis, phlyctenular conjunctivitis ; in purulent conjunctivitis and 

 inflammation of the lacrymal sac ; in acute abscesses formed in the 

 lymphatic glands, the parotid gland, the tonsils, the mammae, etc. ; 

 in metastatic abscesses and purulent collections in the joints ; in em- 

 pyema ; in infectious osteomyelitis ; and in ulcerative endocarditis. 

 The evidence relating to its presence and etiological import in the 

 last-mentioned affections demands special consideration. 



Infectious osteomyelitis appears from the researches of Becker, 

 Rosenbach, Krause, Passet, and others, to be usually due to the pre- 

 sence of Staphylococcus aureus, although Kraske has shown that in 

 certain cases this is associated with other microorganisms. Becker, 

 who obtained this micrococcus from the pus of osteomyelitis in 1883, 

 was the first to show by experiment that the same affection might be 

 induced in rabbits by injecting cultures of the micrococcus into the 

 circulation, after having crushed or fractured a bone in one of its 

 legs. The animal usually died in from twelve to fourteen days and 

 presented the usual appearances of osteomyelitis at the fractured 

 point. The abundant yellowish-white pus contained the golden 

 staphylococcus which was described by Becker, and subsequently 

 known in the bacteriological laboratories of Germany as the " mi- 

 crococcus of infectious osteomyelitis." Becker's experimental re- 

 sults have been confirmed by Krause and Rosenbach; and Rodet, by 

 injecting smaller quantities of a culture into the circulation, has suc- 

 ceeded in producing an osteomyelitis without previous injury to the 

 bone. 



